November 30, 2023
Scientists observed flocks of Canada geese before and after a population-management cull in which about 20% of the birds were killed. In such a situation, some animals species increase “social connectivity”—mixing with many new individuals—which can increase the transmission of infectious diseases.
“They are socially conservative: They keep calm and carry on, responding to losses in the flock by [buttressing] existing ties rather than greatly expanding their social network.
They are culled in various parts of the U.K., including at the Cotswold Water Park, where this study took place.
Reducing the size of the population is a common method to reduce disease transmission. In some species, this can backfire, because individuals respond by forming multiple new social connections—which can increase the spread of disease.
In contrast, after short-term adjustments to restore their social network, this population of Canada geese were robust to the effects of culling; predominantly strengthening existing “friendships” rather than forming lots of new associations, and thus reducing the potential for an increased risk of disease transmission.
The researchers say their findings highlight the importance of understanding the social behavior of different species when planning management interventions such as culling.
The research was funded by the University of Exeter and the Animal and Plant Health Agency.
The paper, published in the Journal of Applied Ecology, is entitled: “Culling-induced perturbation of social networks of wild geese reinforces rather than disrupts associations among survivors.”
Research contact: @EurekAlert